Sophia it might not help you feel better right now but I wanted to let you know that I have been in a very similar position to you. When my eldest son was born I started planning my sway. We were going to start trying for a girl once my son was 8 months old. However, a slightly drunken night (one attempt plus j+d!) resulted in me being pregnant. I was still breastfeeding and only had one attempt so I thought i was in with quite a good chance of having a girl. I was, however, really mad with myself for not swaying esp as I had planned it all so thoroughly.
I had a boy. I can honestly say I do not regret him being a boy for a second. He is nothing like my eldest, they complement each other and are best friends. I wouldn't send him back!
I do still want a girl and five years on, we are trying for one. I just wanted to let you know that even if you have another boy, he is meant to be in your family and I guarantee you will love him to bits. My DH said no more, but I managed to twist his arm ;)